\begin{table}[htbp]\centering
\def\sym#1{\ifmmode^{#1}\else\(^{#1}\)\fi}
\caption{Effect of MPD on the logarithm of gross prices}
\begin{tabular}{l*{4}{c}}
\toprule
                    &\multicolumn{1}{c}{(1) Gasoline}&\multicolumn{1}{c}{(2) Diesel}&\multicolumn{1}{c}{(3) Gasoline}&\multicolumn{1}{c}{(4) Diesel}\\
\midrule
MPD                 &     -0.0296\sym{***}&     -0.0235\sym{***}&     -0.0307\sym{***}&     -0.0278\sym{***}\\
                    &   (0.00018)         &   (0.00016)         &   (0.00071)         &   (0.00054)         \\
\midrule
Observations        &     4128742         &     4727297         &      359372         &      389625         \\
Adjusted \(R^{2}\)  &       0.831         &       0.806         &       0.815         &       0.744         \\
\bottomrule
\multicolumn{5}{l}{\footnotesize Standard errors in parentheses}\\
\multicolumn{5}{l}{\footnotesize SEs are clustered at the fuel station level.}\\
\multicolumn{5}{l}{\footnotesize \sym{*} \(p<0.10\), \sym{**} \(p<0.05\), \sym{***} \(p<0.01\)}\\
\end{tabular}
\end{table}
